Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

fix(agg): fix first_value and last_value to not ignore NULLs #19275

Closed
wants to merge 7 commits into from

Conversation

stdrc
Copy link
Member

@stdrc stdrc commented Nov 6, 2024

I hereby agree to the terms of the RisingWave Labs, Inc. Contributor License Agreement.

What's changed and what's your intention?

To align behavior with PG, we should not ignore NULLs when computing first_value and last_value.

This PR affects batch aggregate, batch over window. Also, a previous PR #19233 has already changed the behavior of streaming over window to the correct one.

Fixes #18927.

Checklist

  • I have written necessary rustdoc comments
  • I have added necessary unit tests and integration tests
  • I have added test labels as necessary. See details.
  • I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
  • My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
  • All checks passed in ./risedev check (or alias, ./risedev c)
  • My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)
  • My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

  • My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.

Signed-off-by: Richard Chien <stdrc@outlook.com>
Copy link
Member Author

stdrc commented Nov 6, 2024

@github-actions github-actions bot added the type/fix Bug fix label Nov 6, 2024
@stdrc stdrc changed the title fix first_value and last_value to not ignore NULLs fix(agg): fix first_value and last_value to not ignore NULLs Nov 6, 2024
@stdrc stdrc marked this pull request as ready for review November 6, 2024 07:50
Copy link
Member

@BugenZhao BugenZhao left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Is this considered a breaking change? Do we use them internally as well?

Signed-off-by: Richard Chien <stdrc@outlook.com>
Signed-off-by: Richard Chien <stdrc@outlook.com>
Signed-off-by: Richard Chien <stdrc@outlook.com>
Signed-off-by: Richard Chien <stdrc@outlook.com>
Signed-off-by: Richard Chien <stdrc@outlook.com>
Signed-off-by: Richard Chien <stdrc@outlook.com>
@stdrc
Copy link
Member Author

stdrc commented Nov 11, 2024

The initial fix is not correct for first_value because of the internal mechanism of aggregate macro. Later commits introduced a new short_if macro argument so that first_value can be implemented via immediate shortcurcuiting.

@stdrc
Copy link
Member Author

stdrc commented Nov 11, 2024

Superseded by #19332

@stdrc stdrc closed this Nov 11, 2024
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
Development

Successfully merging this pull request may close these issues.

last_value different result from mv and ad hoc query
3 participants